The Tories yesterday accused the government of trying to "fix" the social class intake at some of Britain's top universities after it emerged last month that funding was being provided for medical students with lower than the standard minimum A-level grades.

Medical degrees have long been dominated by middle-class students. The government and Hefce, the university funding body, say that such funding, in the form of grants, is an attempt to give students with the potential to excel as doctors more support once they get to university.

Last month, the higher education minister, Alan Johnson, disclosed in an answer to a written question that places for around 80 students holding less than the usual requirement of three C-grades would be subsidised in 2004-05, to help ensure that they did not drop out.

Around 20 universities including Oxford, Cambridge, Imperial College and University College London are involved in the scheme, which funded 480 full-time medical students in 2003-04.

Last year, £126,092 was allocated to the project and a further £21,950 of Hefce's £159m budget will be spent in the next academic in a bid to get more working-class students through university.

Chris Grayling, the higher education spokesperson for the Conservatives, said: "It is quite absurd that the government is paying universities to admit students without the level of exam passes that they would normally need to study medicine.

"We should not be compromising our normal standards for medical students just to help meet the government's political targets in higher education.

"This also means that top quality students with good exam results are being denied the chance to study at leading medical schools simply because their social background doesn't fit the government's plans.

A spokeswoman for Mr Johnson said: "The truth is, the money allocated for widening participation is not an incentive for universities to recruit students with lower A-level scores. It is money which assists universities with the additional costs of retaining able students from disadvantaged backgrounds once they have been recruited.

"Universities will always recruit students they see as having the talent and potential to succeed - it is not in their interest to recruit them otherwise. Medicine remains an extremely competitive subject."

A Hefce spokesman said: "Many universities with our support are committed to broadening the range of medical students to reflect better the needs of the diverse communities which are served by the NHS.

"Admissions decisions are a matter for the universities. They will make these decisions in the light of the particular circumstances of individual applicants and their potential to succeed."